My wife and I daily 350 five speed trucks. It's the only way I'd go. RichLo is on point, however, I have no plans to mod ours. I feel they're fine as is. Clutch on my wife's truck is easier to engage & use than my truck. I think her slave & clutch master cylinder are original. My stuff has been replaced and has sucked a bit more than hers ever since. However, my truck was always a bit firmer. Perhaps if you've got a truck with an external slave like we do, purchase stuff for '92 & up? Not sure if there are any differences or if I was just another victim of the Chinaexpress.
Both our trucks have the 5LM60 transmission. They're supposed to be weaker than the NV3500 and harder to rebuild due to complexity. I think mine has been rebuilt. Wife's truck has what sounds like a death rattle if you start out too strong or if you dig your foot in the throttle below 1,000 rpm. Hers also has a bit of a howl or groan in any gear except direct or OD. My truck only has a hint of the death rattle and none of the groan, why I suspect mine has been rebuilt. Her counter & input shaft's bearings must be getting worn or it was allowed to run low on oil.. However, neither leak fluid and hers hasn't scattered like a jigsaw puzzle thrown into the wind. She's put 15k on it over two years this way and it's got a total of 215k and 29 years on it. So I'd say they're pretty durable. Both still shift and feel great. I beat on 'em both from time to time too. For safety sake, I wait until her's is above 1000rpm before I trample the throttle. We've taken both on road trips close to 1000 miles, transmission concerns were least of our thoughts.
